The invention relates to a resilient molluscan protein, corresponding polypeptides, and nucleic acids encoding the same.
The inner hinge ligament of bivalve molluscs opposes the action of the adductor muscles. This arrangement permits the opening and closing of the shell. In scallops, the apparatus has evolved for swimming (Vogel, Nature, 385:21, 1997). By opening and closing their shells about four times per second, scallops swim a few meters at a time to escape slow-moving predators such as starfish. The scallop ligament is almost entirely protein and its relatively low extent of mineralization compared to the ligaments of other molluscs is thought to contribute to its high resilience (96% recovered work), which is extraordinary even by molluscan standards (Kahler et al., Biol. Bull., 151:161, 1976). The major component of all inner hinge ligaments is the protein abductin (Kelly et al., Science, 155:208, 1967). The physical properties of the ligament suggest that the resilience is entropy based (Alexander, J. Exp. Biol., 44:119, 1966) and that abductin is lightly crosslinked (Anderson, Nature, 216:1029, 1967; Thornhill, Biochemistry, 10:2644, 1971).